Very nice, Si:)
I disagree with your comment, re not good enough. Have confidence in your abilities and style.
Your not making one of millions of chinese tat, which by the way come no where near your efforts.
You are making one off hand crafted items, unique to you.
Its a piece of 3D art, look upon your efforts as such.
They are worth, not what you think they are worth, but what the buyer is willing to pay for a piece of unique art.
I myself like them very much.
As to the suggestion of a transparent cover to compliment and keep the dust off, then next time your in the local supermarket, or pound shop, have a look at all the transparent containers, (with or without contents, which grace the shelves. There are so many of all different styles and shapes, the probability of finding one to suit, I'd say are high. I've done this over the years and paid very little for them, even if the family had to eat the contents first. Just requires a different way at looking at packaging, and you being a keen recycler, should have no problem. The only thing is I get some funny looks as I stand in the supermarket turning various clear containers every which way while mumbling to myself. Think outside the cube, so to speak.
Think Positive, and keep up the fantastic work.
Think twenty five quid for one of your wee diorama jetties is rock bottom. I'd gladly pay that and more for one, if I lived anywhere near the UK.
cheers
vnkiwi